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%I #10 Oct 25 2015 17:58:52
%S 1,111,41114,1411141,20141114102,12120141114102121,
%T 24012120141114102121042,142401212014111410212104241,
%U 41424012120141114102121042414,314142401212014111410212104241413,4131414240121201411141021210424141314,30413141424012120141114102121042414131403
%N Minimal nested palindromic base-5 primes with seed 1; see Comments.
%C Using only base-5 digits 0,1,2,3,4, let s be a palindrome and put a(1) = s. Let a(2) be the least palindromic prime having s in the middle; for n > 2, let a(n) be the least palindromic prime have a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested palindromic base-5 primes with seed s.
%H Clark Kimberling, <a href="/A262641/b262641.txt">Table of n, a(n) for n = 1..300</a>
%e a(3) = 41114 is the least base-5 prime having a(2) = 111 in its middle.
%e Triangular format:
%e 1
%e 111
%e 41114
%e 1411141
%e 20141114102
%e 12120141114102121
%e 24012120141114102121042
%t s = {1}; base = 5; z = 20; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#, base]], base]] &];
%t AppendTo[s, FromDigits[IntegerDigits[tmp, base]]], {z}]; s (* A262641 *)
%t Map[FromDigits[ToString[#], base] &, s] (* A262642 *)
%t (* _Peter J. C. Moses_, Sep 01 2015 *)
%Y Cf. A261881 (base 10), A262627, A262642.
%K nonn,easy,base
%O 1,2
%A _Clark Kimberling_, Oct 24 2015
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